Re: U1 fried

Jerry Gaffke
 

Better be a pretty darn fast fuse.

I'll go with an 8 ohm 1/2 watt series resistor to limit current.
At least till I find a good source for TDA2822M chips.
I'm fairly certain that resistor will offer sufficient protection.

Jerry


On Wed, Feb 28, 2018 at 03:51 pm, Clark Martin wrote:
The TDA2822M data sheet lists an absolute maximum one amp output output current.  Since this chip is apparently prone to blowing out on short circuit I would add a .5A fast blow fuse in the speaker line, between the PCB and the headphone jack.  It doesn’t need a fuse holder, it could be soldered in (using a fuse with pigtail leads).  It would still be easier and cheaper to replace than the amp IC.
 
I’ll likely add this mod to my µBitx.  I don’t intend to short it out but then almost no one does.
 
 

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